In-plane spin reorientation transitions in epitaxial Fe(110)/GaAs(110) films

Epitaxial Fe films in a thickness range from 4 to 64 monolayers (ML) were g rown by molecular beam epitaxy on GaAs(110) at room temperature. The growth was characterized by reflection high energy electron diffraction. The magn etic in-plane anisotropy was investigated by alternating gradient magnetome try in a temperature range from 150 to 295 K. For a 64 ML thick Fe(110) fil m the [001] axis is the easy axis, the [-110] the intermediate axis, and th e hard axis is between [-110] and [-111]. For Fe films with a thickness bel ow 24.2 +/-1.2 ML the [-110] becomes an easy axis at room temperature. A 24 ML Fe film shows a reorientation of the easy axis with decreasing temperat ure: Above the critical temperature of (251 +/-3) K [-110] is the easy axis , for lower temperatures it becomes an intermediate axis. (C) 2001 American Institute of Physics.